I got a n*m matrix updated in realtime (i.e. about every 10ms) with values between 0 and 1024, and I want to work out from that matrix a multitouch trackpad behaviour, which is:

• generate one or more points on the surface given the values on the matrix,
• make this or those point as big as the value can be.

For example here is a few lines of a 9x9 matrix updates, and we can consider the following matrix as an example (with a touch in the middle):

[ [ 12,  7,12 ],
  [ 12,129,19 ],
  [ 12, 11,22 ] ]

I actually don't have a clue where to begin with, or what kind of algorithm or theory to look for on Internet. I'd be really glad to have pointers to documentation, theory or anything that could put me on the way.

Thanks!